The present invention relates generally to exercise devices, including exercise cycles, and more particularly to support devices commonly known as bicycle trainers, including an adjustable resistance producing unit.
For many years, bicycle trainers have been used by bicycling enthusiasts to support their bicycles for stationary riding. Rather than ride in cold or rainy weather, a cyclist can use the trainer to ride indoors and obtain an aerobic, cardiovascular workout. Bicycle trainers also obviate the need for purchasing a separate stationary bicycle for persons who want to occasionally work out while, for example, reading or watching television. Regardless of the reasons for its use, a bicycle trainer should be easy to use and, to the extent possible, simulate bicycle riding on the open road.
A typical bicycle trainer has a frame onto which a user mounts a bicycle. The rear wheel of the bicycle contacts a roller or like mechanism connected to a resistance unit. The existing technologies used in bicycle trainers and many other forms of exercise equipment to provide resistance include: frictional systems that use, for example, belts and pulleys; magnetic systems that use permanent and electromagnets; and fan units. Resistance to exercise and, in the case of bicycle trainers, to the rotation of the rear wheel may be adjustable, and should provide smooth action at various speeds. In addition, it would be desirable for a resistance unit to provide increased resistance as the rotation of the wheel is increased, so that more energy is required to pedal the bicycle and the rider receives a greater workout. As fitness improves, i.e., as a target rpm or cadence is achieved and can be maintained, it would be advantageous to increase resistance to improve a rider's speed.
Resistance units that employ the technologies noted above, although they may include variable resistance, often do not provide smooth action at varying speeds, particularly at transitions to and from various speeds (or rpm), and can also be very noisy.
It is known that fluids can be used as a medium for providing resistance. However, there is no bicycle trainer available currently that effectively uses a fluid in a resistance unit to provide smooth, quiet, adjustable resistance.